Internally fired perforating gun



May 20, 1952 1 Q Tow 2,597,409

INTERNALLY FIRED PERFORATING GUN Filed Sept. 20, 1946 lNvENToR JAMES o. Tow

ATTORNEY Patented May 20, 1952 UNIT-Efo STATES PATENT orgies INTERNALLY FIBED PERFQRATING GUN .laines 0. Tow, Huntington Park, Qalit. assigner to4 McCullough Tool Company, Los Angeles, Qalif., a corporation of Nevada Application September 20, 19416, Serial Ngo. 698,225

(C1. 16de-0.51`

14 Qlaims. 1

My invention relates in general to. guns ior firing projectiles, and relates in particular to gunsy for use in perforating. well casing by the firing oi a projectile therethrough.

It, is. an object ci the invention to provide a gun having a firing chargeoi powder disposed behind a projectile and a cooperative arrangement. of. parts whereby the firing charge. is errploded by rearward movement. oi the. projectile by force applied near the rear end of. the projectile or at. a point spaced rfrom its front end,

. small passage in the gun body.

so that the force employed for the. rearward movement of the projectile will be eiliciently utilized because of the small loss of pressure out through, the front end of the bore 0f 'the gun barrel which receives the projectile It is a further object oi the invention to provide a gun and projectile assembly wherein a spatial enlargement is provided in the gun at a point. spaced from the. front. end of the. projectile, and wherein the projectile has a projecting wall extending into this spatial enlargement soV as to serve as the rear wall thereof, there being means rior applying an ignition effect in this. space or chamber formed by the cooperative relation of the. projectile and the. spatial enlargement. This It is a further object of the invention to.. pro.- vide a simple gun and projectile assembly of the character hereinbefore described, wherein simplicity andA economy of manufacture are at,- tained,` this simplined'forrn of the invention havT ine a replaceable gun barrel which nts into. a laterally directed opening in the body, the

.body havinga passage therein through which the ignition -eieot or explosion of. a priming' charge is corldlucted` and the replaceable barrel having therein passage means communicating with the passage of the gun body for carrying Y the ignition eiect to the side of the projectile ignition effect may be produced or exerted by i the ring of a small amount of powder in the spatial enlargement or the products of coinbustion from the ring of a charge ci powder in a separate chamber or passage may be conducted into the spatial enlargement so that the force thereof will act against the projecting wall on the projectile and thereby drive the projectile rearwardly so that the firing charge of powder in the ring charge chamber willige exploded and the projectile driven outwardly at high velocity through the gun bore.

It is a further object of the invention to provide a gun and projectile arrangement wherein the projectile has. on the rearward portion thereof a ring or aange and rneans. are provided lor exerting a force rearwardly against this ring, or against the shoulder provided thereby to drive the ring rearwardly, l

VA further object of the invention is to provide a gun and projectile arrangement wherein aV ring vis tightly but removably secured to the'rearward portion of the projectile. means are-*provided .for exerting a force against the ring to move the ring and the projectile or the ring alone rearwardly so as to explode the tiring charge. the force of which firing charge will drive the projectile forwardly, canse its separation from the ring, and impel it out through the slln'bore' at high velocity. v

and to the ring or other projection thereon, whereby the ring and the projectile or the ring alone'will be driven rearwardly to cause exa plosion of the firing charge in the firing charge chamber lying behind the projectile.

Further objects and advantages of the inven: tion may be brought out in the following speci-,-

A ication, whereinV l have employed specific and detailed description for; the purpose of 4fully distclosing the invention without placing limita? tion on the scope thereof set forth in the appended alea ,irnsrev Referring to the drawings which are for illus-f trative purposes only;

Fig. 1 is a fragmentary longitudinal section showing a gun body embracing a preferred embodiment of my invention, l

Fig. `2 is a cross section taken en a plane indicated bythe line 2:-.2 of 1 Fig. 3 is a fragmentary sectional View showe ing a portion of a gun body andan insertable or replaceable gun barrel therein, embodying my invention.

In Fig. 1 I show a portion o f a gun body Il which; in accordance with accepted gun practice, may comprise a cylindrio body of steel. This gun body has', leading in from the side wall thereof, openings l2 to receive projectiles I3. Each opening I2 comprises a bore er cylindric space' ld and a spatial enlargement I5 at the rear` end ,of the bore' Hl, @rearwardly of the spatial enlargement I5 there is in the body Il a ring charge chamber I6, the rear wall of which chamber I6 is formed by a plug I1 which is threaded into the body II and serves as a removable closure providing access to the firing charge chamber I6 and to the inner end of the opening I2 which comprises the bore I4 and the spatial enlargement I5. In the form of the invention shown, the side wall I8 of the spatial enlargement I is continuous with the side wall I9 of the firing charge chamber.

Each projectile I3 has thereon a projection which extends outwardly into the spatial enlargement I5 so as to provide on the rearward portion of the projectile I3 a forwardly facing shoulder or face against which pressure may be applied to move the projectile I3 rearwardly for the purpose of exploding the powder charge 20. In the specific form of the invention shown, the spatial enlargement I5 is cylindrical and is coaxial with the bore I4. The projection on the projectile I3 consists of a ring 2|, the outer wall surface of which is contiguous to the wall I8 of the spatial enlargement I5 and the innerA surface of which in the preferred practice of the invention grips fairly tightly the rear portion of the cylindric face ofthe projectile I3. The rear end of the ring 2| has therein an annular channel 22 so as to form a peripheral rearwardly faced lip 23 at the rear end of the ring 2|.

In the gun body II there is, in duplicate, a priming charge chamber or passage 24 extending longitudinally of the gun body |I and communicating through ducts 25 with each spatial enlargement I5 ahead of each ring 2|. When the gun is loaded for use, the plug I1 is removed, and the projectile I3 with its ring 2| is moved through the firing charge chamber I6 into the position shown, the firing charge 2Il is installed and the plug I1 then screwed into place. A seal 2S comprising a plug or disc is then placed so as to close the outer end of the bore I4 and sections of explosive priming cord 21 are placed in the passages 24. The firing of the gun is accomplished by igniting the priming cords 21 by any of the ignition means including caps, fuses, electrical firing devices, etc., now known to the art and therefore not shown in the present application. The combustion products from the explosion of the priming cords 21 is transmitted through the ducts 25 to the forward end of the spatial enlargement I5 and ahead of the ring 2|, this explosive force of the combustion products there acting to drive the ring 2| rearwardly. In the preferred practice of the invention, the ring 2| is secured to the projectile I3 in such a manner that the projectile I3 will be Ycarried rearwardly with the ring, thereby suddenly compressing the powder charge 20, thereby causing the firing charge to explo'del and drive the projectile I3 and the ring 2| forwardly. The ring 2| stops when it reaches the forward end of the spatial enlargement I5 and closes the mouths of the ducts 25. The force of the explosion of wardly with the ring 2| when the force of the priming charge 21-21 is applied to the front face of the ring 2| For example, there may be a threaded engagement between the ring 2| and the projectile I3 of sufficient strength to attain the desired releasable connection between these parts, or the ring 2| may be pressed, sweated, soldered or brazed on the rear end of the projectile I3.

In the form of the invention shown in Fig. 3, I provide a gun body II having at least one transverse opening 30 and at least one removable gun barrel 3|. The recess 30 and the gun barrel 3| are cylindrical and are of such cooperative size thatthe gun barrel 3| will fit snugly in the recess 30. IThe gun barrel 3| includes elements previously described in detail with relation to Figs. 2 and 3, and accordingly these parts will be identified by the same numerals andthe detailed description thereof will not be repeated.

The 'gun body I I' has therein an axial passage 24' which intersects the median portion of the recess 3|. An annular channel 32 is formed in the exterior of the gun barrel 3| in a position to communicate with the passage 24', and the gun barrel 3| also has an ignition passage 25 leading inward from the channel 32 to the front end of the spatial enlargement I5. In the operation of this form of the invention, an ignition charge of powder 35 is placed in the forward portion of the spatial enlargement I5 ahead of the ring 2| and means are provided for the firing of this powder charge 35 so that the force of its explosion dwill drive thepring 2| and the projectile I3 rearward to cause explosion of the firing charge 20 disposed in the firing charge chamber I6 behind the projectile I3 and the ring 2|.A The specific means which I have provided for the firing of the powder charge 35 includes the duct 25 and the passage 24 whereby an ignition effeet may be transmitted to the powder charge 35. For example, a charge of powder may be exploded in the passage 24 or in a chamber, not shown, communicating with this passage 24'. Combustion products therefrom, including pressure and ame, are transmitted throughthe duct 25 to the powder charge 35, causing the same to explode. The explosion of the powder charge 35 serves as an ignition means for the firing charge 20, since the force of its explosion drives the ring-2| and the projectile I3 rearwardly, It will be v,understood that in one practice of the invention, the powder charge may be omitted and the `the firing charge 20 separates the projectile I3 from the ring 2| and drives the same at high velocity out through the bore I4. A feature of the invention is that, not only are the advantages of driving the projectile I3 rearwardly obtained,

but the projectile I3 is given an initial impetus explosive kforce transmitted from the passage 24' through thevduct 25 to the spatial enlargement I5 ahead of the ring 2| isl utilized to drive the ring 2| andthe projectile rearwardly.

I claim as my invention:

.1 .In a gun and projectile arrangement, the combination of a body having a projectile receiving bore, a spatial enlargement at the rear end of said bore, a firing charge chamber communicating with the rear end of said bore,l and a passage communicating with ,saidy spatial enlargement; a projectile in said bore having thereon a projection extending outwardlyY into said spatial enlargement rearwardly of said communication ofrsaid passage with said spatial enlargement, the transverse area of said projection being substantially. equal to the transverse area of said spatial enlargement, and said projection being releasable from said projectile as said projectile moves out through said bore; a firing charge Yin said chamber; and means for applying pressure through said passage into said spatial enlargement ahead of said projection, to drive the projectile rearwardly whereby said firing charge will be exploded.

2. In a gun and projectile arrangement, the combination of a body having a projectile receiving bore, a spatial enlargement at the rear end of said bore, a ring charge chamber communicating with the rear end of said bore, and a passageV communicating with said spatial enlargement; a projectile in said bore having thereon a projection extending outwardly into said spatial enlargement rearwardly of said communication of said passage with said spatial enlargement, the transverse area of said projection being substantially equal to the transverse area of said spatial enlargement, and said projection being releasable from said projectile; a firing charge in said chamber; an ignition charge of powder; means for ring said ignition charge; and wall means for directing the products of combustion from said ignition charge into said passage.

3. In a gun and projectile arrangement, the combination of: a body having a projectile receiving bore, a spatial enlargement at the rear end of said bore, a firing charge chamber communicating with the rear end of said bore; a projectile in said bore having thereon a projection extending outwardly into said spatial enlargement, the transverse area of said projection being substantially equal to the transverse area of said spatial enlargement, and said projection being releasable from said projectile; a ring charge in said chamber; an ignition charge; means for ring said ignition charge; and wall means for directing the products of combustion from said ignition charge into said spatial enlargement ahead of said projection.

4. In a gun and projectile arrangement, theY combination of: a body having a projectile receiving bore, a spatial enlargement at the rear end of said bore, a ring charge chamber communicating with the rear end of said bore; a ring charge in said chamber; a projectile in said bore having thereon a projection extending outwardly into said spatial enlargement, the transverse area of said projection being substantially equal to the transverse area of said spatial enlargement, and said projection being releasable from said projectile as said projectile moves out through said bore; means for accumulating a fluid pressure; and means for directing said fluid pressure into said spatial enlargement ahead of said projection to drive the projectile rearwardly and thereby cause explosion of said ring charge.

5. In a gun and projectile arrangement, the combination of: a body having a projectile receiving bore, an annular spatial enlargement at the rear end of said bore, a ring charge chamber communicating with the rear end of said bore, and a passage communicating with said spatial enlargement; a projectile in said bore having thereon a ring extending outwardly into said spatial enlargement rearwardly of said communication of said passage with said spatial enlargement, said ring having a transverse area substantially equal to the transverse area of said spatial enlargement, and said ring being separable from said projectile as said projectile passes out through said bore; a firing charge in said chamber; and means for applying pressure through said passage into said spatial enlargement ahead of said ring, to drive the projectile rearwardly, whereby said firing charge will be exploded.

6. In a gun and projectile arrangement, the combination of: a body having'a projectile re- 6 ceiving bore, an annular spatial enlargement at the rear end of said bore, a firing charge chamber communicating with rthe rear end of said bore, and a passage communicating with said spatial enlargement; a projectile in said bore having thereon a ring extending outwardly into said spatial enlargement rearwardly of said communication of said passage withfsaid spatial enlargement, said ring having a transverse area substantially equal to the transverse area of said spatial enlargement, and said ring being separable from said projectile; a firing charge in said chamber; an ignition charge of powder; means for ring said ignition charge; and wall means'for directing the products .of combustion from said ignition charge into said passage.

'7. In a gun and projectile arrangement, the combination of a body having a projectile receiving bore, an annular spatial enlargement at the rear end .of said bore, a ringV charge chamber .communicating withV the rear `end of said bore; a `projectile in said bore having thereon a ring extending outwardly into said spatial enlargement, said ring having -a transverse area substantially equal to the transverse area of said spatial enlargement, and said ring being separable from said projectile; a firing charge in said chamber; an ignition charge; means for firing said ignition charge; and walls defining passage means which direct the products of combustion from said ignition charge into said spatial enlargement ahead of said ring. Y

8. In a gun and projectile arrangement, the combination of: a body having a projectile receiving bore, an annular spatial enlargement at the rear end of said bore, and a firing charge chamber communicating with the rear end of said bore; a ring charge in said chamber;a pro'- jectile in said bore having thereon a ring extending outwardly into said spatial enlargement, said ring having a transverse area substantially equal to the transverse area of said spatial enlargement, and said ring being separable from said projectile; means for accumulating a fluid pressure; and means for directing said uid pressure into said spatial enlargement ahead of said ring to drive the projectile rearwardly and thereby cause explosion of said firing charge.

9. In a gun and projectile arrangement, the combination of: a body having a bore to receive a projectile and a firing charge chamber communicating with the rear end of said bore; a firing charge in said chamber; a projectile in said bore having at its rear end an annular flange which expands behind the rear end of said bore within said firing charge chamber and substantially touches the side wall of said chamber; and means comprising a source of fluid pressure separate from said ring charge adapted to apply pressure against the front of said flange to move said projectile rearwardly and thereby cause explosion of the firing charge disposed in said firing charge chamber.

10. In a gun and projectile arrangement, the combination of: a body having a bore to receive a projectile and a ring charge chamber communicating with the rear end of said bore; a firing charge in said chamber, a projectile in said bore having at its rear end an annular flange which expands behind the rear end of said bore Within said firing charge chamber and substantially touches the side wall of said chamber; an ignition charge of powder; means for firing said ignition charge; and means comprising walls for directing the products of combustion from said 7 ignition charge against the front face of said flange to drive said projectile rearwardly and thereby accomplish explosion of said firing charge.

1l. In a gun and projectile arrangement, the combination of: a body .having a projectile receiving bore, a spatial enlargement at the rear end of said bore, a ring charge chamber communicating with the rear end of said bore; a projectile in said bore having thereon a projection extending outwardly into said spatial enlargement, the transverse area of said projection being substantially equal to the transverse area of said spatial enlargement, and said projection being releasable from said projectile; a ring charge in said chamber; and ignition producing means acting in said spatial enlargement ahead of the rear end of said projection.

12. In a gun and projectile arrangement, the combination of a body having a projectile receiving bore, a spatial enlargement at the rear end of said bore, a firing charge chamber communicating with the rear end of said bore; a projectile in said bore having thereon a projection extending outwardly into said spatial enlargement, the transverse area of said projection being substantially equal to the transverse area of said spatial enlargement, and said projection being releasable from said projectile; a ring charge in said chamber; an explosive in said spatial enlargement ahead of said projection and means to ignite said explosive.

13. In a gun and projectile arrangement, the combination of: a body having a projectile receiving bore, a spatial enlargement at the rear end of said bore, a ring charge chamber communicating with the rear end of said bore; a firing .charge in said chamber, a projectile in said bore having thereon a projection extending outwardly into said spatial enlargement, the transverse area of said projection being substantially equal to the transverse area of said spatial enlargement, and said projection being releasable from said projectile; an ignition charge; and walls forming an ignition passage connecting said ignition charge and said spatial enlargement ahead of the rear end of said projection.

14. In a gun and projectile arrangement, the combination of: a body having a projectile receiving bore, an annular spatial enlargement at the rear end of said bore and a ring charge chamber at the rear end of said bore; a firing charge in said chamber; a projectile in said bore; a member at the rear end of said projectile providing an annular wall which projects radially in said spatial enlargement, said member having a transverse area substantially the same as the transverse area of said spatial enlargement; and walls forming a passage communicating with said spatial enlargement ahead of said annular Wall for transmission of pressure to the front face of said member.

JAMES O. TOW.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Martin DEC. 23, 1947 

